What other methods you are using for backlinking? If you are relying on only directory submission then you won't get too far. You need to use other SEO methods as well like article submssion, slide sharing, image sharing, classifieds, business listing, forums.
Its waste of time to do directories and it is very slow process better you try Profile creation to get backlinks. While you are creating profile creation you need to add the link of your website so you will get backlinks form that site.